diff --git a/lib/Slic3r/Print.pm b/lib/Slic3r/Print.pm
index c0ed2e11..d5884c10 100644
--- a/lib/Slic3r/Print.pm
+++ b/lib/Slic3r/Print.pm
@@ -662,10 +662,9 @@ sub make_skirt {
     # skirt may be printed on several layers, having distinct layer heights,
     # but loops must be aligned so can't vary width/spacing
     # TODO: use each extruder's own flow
-    my $region0_config = $self->regions->[0]->config;
     my $first_layer_height = $self->objects->[0]->config->get_value('first_layer_height');
     my $flow = Slic3r::Flow->new(
-        width               => ($region0_config->first_layer_extrusion_width || $region0_config->perimeter_extrusion_width),
+        width               => ($self->config->first_layer_extrusion_width || $self->regions->[0]->config->perimeter_extrusion_width),
         role                => FLOW_ROLE_PERIMETER,
         nozzle_diameter     => $self->config->nozzle_diameter->[0],
         layer_height        => $first_layer_height,
@@ -713,7 +712,7 @@ sub make_brim {
     
     # brim is only printed on first layer and uses support material extruder
     my $flow = Slic3r::Flow->new(
-        width               => ($self->regions->[0]->config->first_layer_extrusion_width || $self->regions->[0]->config->perimeter_extrusion_width),
+        width               => ($self->config->first_layer_extrusion_width || $self->regions->[0]->config->perimeter_extrusion_width),
         role                => FLOW_ROLE_PERIMETER,
         nozzle_diameter     => $self->config->nozzle_diameter->[ $self->objects->[0]->config->support_material_extruder-1 ],
         layer_height        => $self->objects->[0]->config->get_abs_value('first_layer_height'),
@@ -801,7 +800,7 @@ sub write_gcode {
             if $self->has_support_material;
         printf $fh "; first layer extrusion width = %.2fmm\n",
             $self->regions->[$region_id]->flow(FLOW_ROLE_PERIMETER, $layer_height, 0, 1)->width
-            if ($self->regions->[$region_id]->config->first_layer_extrusion_width ne '0');
+            if $self->regions->[$region_id]->config->first_layer_extrusion_width;
         print  $fh "\n";
     }
     
diff --git a/lib/Slic3r/Print/Object.pm b/lib/Slic3r/Print/Object.pm
index bf4c2efb..84dc33b3 100644
--- a/lib/Slic3r/Print/Object.pm
+++ b/lib/Slic3r/Print/Object.pm
@@ -863,11 +863,20 @@ sub generate_support_material {
     return unless ($self->config->support_material || $self->config->raft_layers > 0)
         && $self->layer_count >= 2;
     
+    my $first_layer_flow = Slic3r::Flow->new(
+        width               => ($self->config->first_layer_extrusion_width || $self->config->support_material_extrusion_width),
+        role                => FLOW_ROLE_SUPPORT_MATERIAL,
+        nozzle_diameter     => $self->print->config->nozzle_diameter->[ $self->config->support_material_extruder-1 ],
+        layer_height        => $self->config->get_abs_value('first_layer_height'),
+        bridge_flow_ratio   => 0,
+    );
+    
     my $s = Slic3r::Print::SupportMaterial->new(
-        print_config    => $self->print->config,
-        object_config   => $self->config,
-        flow            => $self->support_material_flow,
-        interface_flow  => $self->support_material_flow(FLOW_ROLE_SUPPORT_MATERIAL_INTERFACE),
+        print_config        => $self->print->config,
+        object_config       => $self->config,
+        first_layer_flow    => $first_layer_flow,
+        flow                => $self->support_material_flow,
+        interface_flow      => $self->support_material_flow(FLOW_ROLE_SUPPORT_MATERIAL_INTERFACE),
     );
     $s->generate($self);
 }
diff --git a/lib/Slic3r/Print/Region.pm b/lib/Slic3r/Print/Region.pm
index ff05d5bc..c587f515 100644
--- a/lib/Slic3r/Print/Region.pm
+++ b/lib/Slic3r/Print/Region.pm
@@ -21,8 +21,8 @@ sub flow {
     if (!defined $config_width) {
         # get extrusion width from configuration
         # (might be an absolute value, or a percent value, or zero for auto)
-        if ($first_layer && $self->config->first_layer_extrusion_width ne '0') {
-            $config_width = $self->config->first_layer_extrusion_width;
+        if ($first_layer && $self->print->config->first_layer_extrusion_width) {
+            $config_width = $self->print->config->first_layer_extrusion_width;
         } elsif ($role == FLOW_ROLE_PERIMETER) {
             $config_width = $self->config->perimeter_extrusion_width;
         } elsif ($role == FLOW_ROLE_INFILL) {
diff --git a/lib/Slic3r/Print/SupportMaterial.pm b/lib/Slic3r/Print/SupportMaterial.pm
index 0dae19e1..b6d793ee 100644
--- a/lib/Slic3r/Print/SupportMaterial.pm
+++ b/lib/Slic3r/Print/SupportMaterial.pm
@@ -9,9 +9,11 @@ use Slic3r::Geometry::Clipper qw(offset diff union union_ex intersection offset_
     intersection_pl);
 use Slic3r::Surface ':types';
 
-has 'print_config'  => (is => 'rw', required => 1);
-has 'object_config' => (is => 'rw', required => 1);
-has 'flow'          => (is => 'rw', required => 1);
+has 'print_config'      => (is => 'rw', required => 1);
+has 'object_config'     => (is => 'rw', required => 1);
+has 'flow'              => (is => 'rw', required => 1);
+has 'first_layer_flow'  => (is => 'rw', required => 1);
+has 'interface_flow'    => (is => 'rw', required => 1);
 
 use constant DEBUG_CONTACT_ONLY => 0;
 
@@ -385,11 +387,12 @@ sub clip_with_object {
 sub generate_toolpaths {
     my ($self, $object, $overhang, $contact, $interface, $base) = @_;
     
-    my $flow = $self->flow;
+    my $flow            = $self->flow;
+    my $interface_flow  = $self->interface_flow;
     
     # shape of contact area
     my $contact_loops   = 1;
-    my $circle_radius   = 1.5 * $flow->scaled_width;
+    my $circle_radius   = 1.5 * $interface_flow->scaled_width;
     my $circle_distance = 3 * $circle_radius;
     my $circle          = Slic3r::Polygon->new(map [ $circle_radius * cos $_, $circle_radius * sin $_ ],
                             (5*PI/3, 4*PI/3, PI, 2*PI/3, PI/3, 0));
@@ -410,8 +413,8 @@ sub generate_toolpaths {
     );
     
     my $interface_angle = $self->object_config->support_material_angle + 90;
-    my $interface_spacing = $self->object_config->support_material_interface_spacing + $flow->spacing;
-    my $interface_density = $interface_spacing == 0 ? 1 : $flow->spacing / $interface_spacing;
+    my $interface_spacing = $self->object_config->support_material_interface_spacing + $interface_flow->spacing;
+    my $interface_density = $interface_spacing == 0 ? 1 : $interface_flow->spacing / $interface_spacing;
     my $support_spacing = $self->object_config->support_material_spacing + $flow->spacing;
     my $support_density = $support_spacing == 0 ? 1 : $flow->spacing / $support_spacing;
     
@@ -452,11 +455,11 @@ sub generate_toolpaths {
             my @loops0 = ();
             {
                 # find centerline of the external loop of the contours
-                my @external_loops = @{offset($contact, -$flow->scaled_width/2)};
+                my @external_loops = @{offset($contact, -$interface_flow->scaled_width/2)};
                 
                 # only consider the loops facing the overhang
                 {
-                    my $overhang_with_margin = offset($overhang, +$flow->scaled_width/2);
+                    my $overhang_with_margin = offset($overhang, +$interface_flow->scaled_width/2);
                     @external_loops = grep {
                         @{intersection_pl(
                             [ $_->split_at_first_point ],
@@ -476,8 +479,8 @@ sub generate_toolpaths {
             # make more loops
             my @loops = @loops0;
             for my $i (2..$contact_loops) {
-                my $d = ($i-1) * $flow->scaled_spacing;
-                push @loops, @{offset2(\@loops0, -$d -0.5*$flow->scaled_spacing, +0.5*$flow->scaled_spacing)};
+                my $d = ($i-1) * $interface_flow->scaled_spacing;
+                push @loops, @{offset2(\@loops0, -$d -0.5*$interface_flow->scaled_spacing, +0.5*$interface_flow->scaled_spacing)};
             }
             
             # clip such loops to the side oriented towards the object
@@ -500,7 +503,7 @@ sub generate_toolpaths {
             @loops = map Slic3r::ExtrusionPath->new(
                 polyline        => $_,
                 role            => EXTR_ROLE_SUPPORTMATERIAL,
-                flow_spacing    => $flow->spacing,
+                flow_spacing    => $interface_flow->spacing,
             ), @loops;
             
             $layer->support_interface_fills->append(@loops);
@@ -534,7 +537,7 @@ sub generate_toolpaths {
                 my ($params, @p) = $fillers{interface}->fill_surface(
                     Slic3r::Surface->new(expolygon => $expolygon, surface_type => S_TYPE_INTERNAL),
                     density         => $interface_density,
-                    flow_spacing    => $flow->spacing,
+                    flow_spacing    => $interface_flow->spacing,
                     complete        => 1,
                 );
                 
@@ -565,7 +568,7 @@ sub generate_toolpaths {
                 $filler = $fillers{interface};
                 $filler->angle($self->object_config->support_material_angle + 90);
                 $density        = 0.5;
-                $flow_spacing   = $object->print->first_layer_support_material_flow->spacing;
+                $flow_spacing   = $self->first_layer_flow->spacing;
             } else {
                 # draw a perimeter all around support infill
                 # TODO: use brim ordering algorithm
diff --git a/xs/src/Config.hpp b/xs/src/Config.hpp
index 3af99a44..9306a18b 100644
--- a/xs/src/Config.hpp
+++ b/xs/src/Config.hpp
@@ -374,7 +374,7 @@ class ConfigOptionDef
     std::vector<std::string> enum_labels;
     t_config_enum_values enum_keys_map;
     
-    ConfigOptionDef() : multiline(false), full_label(false), full_width(false), readonly(false),
+    ConfigOptionDef() : multiline(false), full_width(false), readonly(false),
                         height(-1), width(-1), min(INT_MIN), max(INT_MAX) {};
 };
 
diff --git a/xs/src/PrintConfig.hpp b/xs/src/PrintConfig.hpp
index 8ac01f50..05380ab1 100644
--- a/xs/src/PrintConfig.hpp
+++ b/xs/src/PrintConfig.hpp
@@ -952,7 +952,6 @@ class PrintRegionConfig : public virtual StaticConfig
     ConfigOptionInt                 fill_angle;
     ConfigOptionFloat               fill_density;
     ConfigOptionEnum<InfillPattern> fill_pattern;
-    ConfigOptionFloatOrPercent      first_layer_extrusion_width;
     ConfigOptionInt                 infill_extruder;
     ConfigOptionFloatOrPercent      infill_extrusion_width;
     ConfigOptionInt                 infill_every_layers;
@@ -976,8 +975,6 @@ class PrintRegionConfig : public virtual StaticConfig
         this->fill_angle.value                                   = 45;
         this->fill_density.value                                 = 0.4;
         this->fill_pattern.value                                 = ipHoneycomb;
-        this->first_layer_extrusion_width.value                  = 200;
-        this->first_layer_extrusion_width.percent                = true;
         this->infill_extruder.value                              = 1;
         this->infill_extrusion_width.value                       = 0;
         this->infill_extrusion_width.percent                     = false;
@@ -1003,7 +1000,6 @@ class PrintRegionConfig : public virtual StaticConfig
         if (opt_key == "fill_angle")                                 return &this->fill_angle;
         if (opt_key == "fill_density")                               return &this->fill_density;
         if (opt_key == "fill_pattern")                               return &this->fill_pattern;
-        if (opt_key == "first_layer_extrusion_width")                return &this->first_layer_extrusion_width;
         if (opt_key == "infill_extruder")                            return &this->infill_extruder;
         if (opt_key == "infill_extrusion_width")                     return &this->infill_extrusion_width;
         if (opt_key == "infill_every_layers")                        return &this->infill_every_layers;
@@ -1052,6 +1048,7 @@ class PrintConfig : public virtual StaticConfig
     ConfigOptionFloats              filament_diameter;
     ConfigOptionFloat               first_layer_acceleration;
     ConfigOptionInt                 first_layer_bed_temperature;
+    ConfigOptionFloatOrPercent      first_layer_extrusion_width;
     ConfigOptionFloatOrPercent      first_layer_speed;
     ConfigOptionInts                first_layer_temperature;
     ConfigOptionBool                g0;
@@ -1142,6 +1139,8 @@ class PrintConfig : public virtual StaticConfig
         this->filament_diameter.values[0]                        = 3;
         this->first_layer_acceleration.value                     = 0;
         this->first_layer_bed_temperature.value                  = 0;
+        this->first_layer_extrusion_width.value                  = 200;
+        this->first_layer_extrusion_width.percent                = true;
         this->first_layer_speed.value                            = 30;
         this->first_layer_speed.percent                          = true;
         this->first_layer_temperature.values.resize(1);
@@ -1242,6 +1241,7 @@ class PrintConfig : public virtual StaticConfig
         if (opt_key == "filament_diameter")                          return &this->filament_diameter;
         if (opt_key == "first_layer_acceleration")                   return &this->first_layer_acceleration;
         if (opt_key == "first_layer_bed_temperature")                return &this->first_layer_bed_temperature;
+        if (opt_key == "first_layer_extrusion_width")                return &this->first_layer_extrusion_width;
         if (opt_key == "first_layer_speed")                          return &this->first_layer_speed;
         if (opt_key == "first_layer_temperature")                    return &this->first_layer_temperature;
         if (opt_key == "g0")                                         return &this->g0;